• 대한기계학회논문집
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• 제1권3호
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• pp.125-130
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• 1977

This is a dimensionless analysis of interior ballistics for the design of gun tube. One of the characteristics of this analysis is to ues the .ETA.$_{j}$ number which means a relative quantity of virtual work to the kimetic energy of projectile at the muzzle. In order to apply the concept of virtual work, it is assumed that the projectile is moved from the beginning to the end of bore under constant pressure of the certain travel distance of projectile. The principle of the analysis is induced from the Le Duc equation, which expresses velocity as a function of projectile travel and is based on the translation of a hyperbolic curve. From this non-dimensional analysis, the optimum design parameters of pressure in the bore, velocity and acceleration of projectile can be obtained from the table of figure without computation. This method was verified by the experimental work.k.

• 문화경제연구
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• 제20권2호
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• pp.3-18
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• 2017

본 연구에서는 콘텐츠산업 인력의 업무 자율성 변화를 분석했다. 한국근로환경조사(2011, 2014) 자료에서 콘텐츠산업 인력과 업무 자율성 변수를 추출하고 이중차감추정법을 활용하여 분석한 결과 전체 표본에서는 콘텐츠산업 인력의 업무 자율성(업무 순서, 업무 방법, 업무속도)에 유의미한 변화가 나타나지 않았다. 반면 최근 콘텐츠업계의 자율성 감소는 논의는 대규모 인력과 자본이 투입되는 경우라는 것을 고려하여 30인 이상 사업체 표본을 대상으로 분석하면 콘텐츠산업 인력의 자율성이 유의미하게 감소한 것으로 나타난다. 업무의 자율성은 직위와 역량과는 정(+)의 관계가, 사업체 규모와는 부(-)의 관계가 나타난다. 본 연구는 그동안 사례 중심으로 논의되어 왔던 콘텐츠산업 인력의 업무 자율성 변화를 실증분석했다는 의의를 가진다. 또한, 인력들의 부여되는 자율성이 콘텐츠 제작 유통 과정에서 긍정적인 효과를 창출하기 위해서는 인력에 대한 보상 및 관리 체계 개선이 수반되어야 함을 제시하였다.

• 한국레이저가공학회지
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• 제4권1호
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• pp.29-38
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• 2001

This work was carried out to investigate the welding behavior of thin A3003 Al alloy sheets by Nd : YAG laser beam. Considering bead shape and mechanical properties, the laser pulse shapes selected were two kinds of 2-division and 3-division by varying power level and pulse duration. In order to obtain optimum conditions, the factorial design method and central composite design method were applied. Tensile test, optical microscopy, micro hardness test and TEM analysis were performed. Due to the annealing caused by thermal effect during laser welding, precipitates were coarsended. The HAZ was softened and failed during tensile test. The hardness of HAZ was lower than that of base metal, since the heat input relieved the work hardening effect and caused grain growth.

• 대한안전경영과학회지
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• 제6권2호
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• pp.251-262
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• 2004

There is boner process of stone manufacturing to become quality down of stone to consolidated micro crack appearance of stone surface and biotite by fire that is to be route process in stone surface by flame of LPG. And then, it is develop that stone surface process equipment by automation for the work method of boner process can be substitute work method by shotball blasting. To developement of equipment, There is to be down noise and dust. Acording to remove calamity growth hazardous substance in the work environment, there is to solve workplace avoidance factor. We have taken Taguchi's parameter design approch, specifically orthogonal array, and determined the optimal levels of stone surface through analysis of the experimental results using SIN ratio.

• 농업과학연구
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• 제42권2호
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• pp.117-124
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• 2015

In forest work, working conditions are very hard to improve. The good posture is believed to bring about direct improvements such as accident prevention. Therefore, this research carried on analysis of working posture in forest work (construct in stepping-stone) using OWAS analysis system. According to the analytical results provided by OWAS, the ratio of category III (Work posture has a distinctly harmful effect on the musculoskeletal system) has shawn that worker 2 was 32.2%, worker 1 was 25.2% and worker 3 was 15.5%. Furthermore, the ratio of category IV (Work posture with an extremely harmful effect on the musculoskeletal system) has shown that worker 2 was 9.8%, worker 3 was 1.4% and worker 1 was 1.2%. According to the OWAS method, percentage of OWAS action categories III and IV in the worker 2 was higher than another workers.

• 실천공학교육논문지
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• 제15권1호
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• pp.183-192
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• 2023

본 연구는 학위연계형 일학습병행제에서 진행하는 오프라인 수업방식인 플립러닝의 성과에 대해서 분석한다. 직업능력향상의 일환으로 수행되는 일학습병행제의 훈련은 철저히 오프라인 방식을 견지해 왔으나, COVID-19와 맞물려 이전과는 달리 보다 적극적으로 온라인 방식을 혼용하는 방향으로 바뀌고 있다. 하지만 학위연계형의 운영은 대학의 학사시스템과 교육방식에 적용을 받으며 실질적으로 일반대학교육과 같은 형태이기 때문에 플립러닝과 같은 교육방식은 새로운 것이 아니다. 따라서 최근 학위연계형 일학습병행제에서 확대적용되고 있는 플립러닝의 교육성과와 보완점을 주말에만 수업이 진행되는 본 제도의 특성을 고려하여 분석해 보는 것이 필요하다. 설문에 기반한 통계분석결과 플립러닝의 성과가 일부 확인되었으며, 그 성과를 높이기 위해서 학습독려와 교수자-학생 간의 커뮤니케이션을 확대하는 구체적인 방안을 지속적으로 찾아가는 것이 필요하다.

• Architectural research
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• 제16권2호
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• pp.75-80
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• 2014

Risks, uncertainties, and associated cost overruns are critical problems for construction projects. Cost contingency is an important funding source for these unforeseen events and is included in the base estimate to help perform financially successful projects. In order to predict more accurate contingency, many empirical models using regression analysis and artificial neural network method have been proposed and showed its viability to minimize prediction errors. However, categorical factors on contingency cannot have been treated and thus considered in these empirical models since those models are able to treat only numerical factors. This paper identified potential factors on contingency in transportation construction projects and evaluated categorical factors using the one-way ANOVA statistical method. Among factors including project work type, delivery method type, contract agreement type, bid award type, letting type, and geographical location, two factors of project work type and contract agreement type were found to be statistically important on allocating cost contingency.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2001년도 학술논문발표회
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• pp.130-135
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• 2001

In this study, I have researched into the causes of defects in apartment house, The results of this study are listed below. (1) Water leakages which result from land sinking and cracks, results of misuse of back filling method, are the main reason of defects in civil engineering work and architectural work. (2) Inexperience and unwillingness are the main reason of defects in plaster work. (3) In windows work and painting work, the main reasons are lacks of precision construction and efflorescence resulting from outdoor air, respectively. (4) Defects in waterproofing work and electric work result from fault construction by low unit Costs. (5) Equipment work requires uses of standardized construction materials and management, and landscape architecture work requires minimizing human mistakes, for instance, degin carelessness. For the reasons stated above, the causes of defects in apartment house are insufficient construction labors, inferior construction materials, urgent construction process time, and conscientiousless industrialists who only seek after a profit margin.

• 한국건설관리학회논문집
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• 제8권3호
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• pp.76-86
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• 2007

건축개발사업은 목적물을 완성시킴으로써 이윤을 창출하는 사업이고, 프로젝트의 성공을 좌우하는 것은 프로젝트 초기에 사업타당성을 정확히 분석하고 예측하는 것에 달려있다. 사업타당성 분실은 본질적으로 현재시점에서 미래예측이라는 불확실성을 내포하고 있으므로 불확실한 상황 하에서 의사결정을 할 수밖에 없다. 이러한 불확실성 하에서의 의사결정방법은 통계학의 확률이론에 기초하고 있지만, 지금까지 사업 타당성 분석은 확률론적 결정방법에 의한 타당성 분석이 아니라 결정론적 방법에 의한 타당성분석을 적용하여 왔다. 따라서 본 연구에서는 초기 사업 타당성 분석 시 프로젝트의 성공을 위해 확률론적 방법에 의한 의사결정을 함으로써, 의사결정 자에게 좀 더 정확하고 신뢰성 있는 자료를 제공할 수 있는 시뮬레이션을 이용한 확률론적 분석방법을 제시한다. 본 연구 결과 확률론적 시뮬레이션 기 법은 건축개발사업의 재무적 타당성 분석 기법으로 적합하다. 중요한 사업 또는 신중한 의사결정시 이 방법을 활용함으로서 정확성과 신뢰성에 근거하여 효율적인 판단이 가능해 질 것이므로 그 활용성이 기대된다.

• 한국보건간호학회지
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• 제23권1호
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• pp.69-77
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• 2009

Purpose: This study was conducted to investigate health problems and factors related to work impairment of nurses working at community health centers. Method: Data were collected from May 2008 to July 2008 using a structured, self - reported questionnaire for general characteristics, work-related characteristics, health problems and work impairment. The subjects were composed of 434 nurses from 25 community health centers in Seoul. Data were analyzed by descriptive statistics, t-test, ANOVA, Pearson's correlation coefficient and multiple regression analysis. Results: For present health problems, shoulder, back and neck pain were ranked the highest at (54.6%), followed by cold, GI trouble, and visual disorders. The average score of work impairment was 24.71($\pm7.14$) out of 50.0. Multiple regression analysis revealed that the major factors that affect work impairment were age and number of health problems, and that these factors explained 15% of the work impairment. Conclusion: Age and number of health problems are the factors that have the greatest influence on work impairment. These findings indicate that the health condition of nurses at community health centers must be considered to improve the overall quality of nursing service.